John Wirth was one of the main writers for Terminator: The Sarah Connor Chronicles, and now he's showrunner of NBC's The Cape, launching Sunday. We caught up with him to ask about moving from killer robots to supervillains. Spoilers ahead...

We caught up with John Wirth at San Diego Comic Con last summer and he gave us an exclusive interview about his work on The Cape, which we decided to save until the show was about to air. So here it is!

We were huge fans of The Sarah Connor Chronicles, so we were excited when we heard you were going to be showrunner over at The Cape. Do the two shows have anything else in common, besides Summer Glau?

[Laughs] I don't know if there really need to be any commonalities, besides Summer Glau. She is a joy. She's such a talented creative unique being, and you know, the funny thing — I was sort of getting a Summer Glau vibe, like I hadn't talked to her for a while, and I sort of thought, "I need to check in with her and see what she's doing." It's the daddy mode in me. So I put a call in to her. And three days later, [The Cape creator] Tom Wheeler called me, and he said, "What are you doing?" I said, "Nothing." He said, "Well, I'm doing this pilot, why don't you come down on the set and see what's going on?" And lo and behold, there's Summer. So I thought it was very serendipitous that I should have gotten that calling and Wheeler calls me, and the whole thing comes together.

How was it coming and taking over after the pilot was already shot?

Well, I didn't come in and take in, I came in in a very similar way that I did on Sarah Connor Chronicles. Tom certainly has more television experience now than Josh [Friedman] had when we started on the Sarah Connor Chronicles. But he's never been in a position where he's had his own show or been expected to run his own show. And just by virtue of having been around a few more years than either of those two guys, I had a bit more experience and had things I could share with them. So on this show, I'm sort of working with Tom and creating a structure that the show can work [with].

So this is a superhero show that's hyper-aware of superhero conventions, because the Cape is an existing comic-book character before the show's protagonist decides to dress up as him. Right?

That's a little bit TBD I would say... we're not quite sure how that comic book is going to play out as the series goes forward. It's certainly an aspect of the world. And it's interesting that this guy has chosen a character from a comic book to sort of embody as a superhero. So I think it's going to be very interesting. When you have a guy who's sort of living out the exploits of a comic book character... there may be a certain rivalry, like who's better? Him or the real guy? And his son, in the pilot, is very into the comic books. There will be a certain amount of expectations on the son's part as to what the Cape should be doing. So I think he'll be critiquing the Cape's performance a little bit.

It's going to be a pretty light show in general, right?

Right. I would say the show will be grounded. Here's the trick — creating a reality for the world of the show, communicating that reality to the audience, and then telling your stories within the boundaries of that reality, so you don't violate it. And that's what we're going to try to do. But in our world, the stakes are real, the consequences are real, the stories have danger elements that are real. And yet there's a kind of a fanciful element to it that's fun. So we won't be doing ha-ha comedy, but there will be funny situations.

So there are going to be villains of the week?

Yeah. I think the idea is there'll be an over-arching story. It won't be as serialized as we started out with Sarah Connor. But there will be serialized aspects to the show. But each week, it'll either be someone in James Frain's world — his character is Peter Fleming, he's sort of the big baddie — it'll be someone dispatched by him, or him, or some other villain.

What do you say to people who feel like they've been burned by superhero shows in the past?

I say, "Sooner or later, one of them's going to work, and be just right." It'll be this one, hopefully.

Do you think this one has the right balance of respect for the mythology without getting too deep?

Yeah, definitely. Tom is a comic book geek, bigtime. All of us have had our own experiences with comic books and superheroes. On the panel I showed a picture of me in my own superhero outfit at age five — and I had my own collection of superhero comics at that time, which I can still remember my father throwing out.